Such machines are already known. They are used as office machines for preparing mail for posting, or else they form a part of a larger installation for automatically processing large volumes of mail and further including a machine for folding and/or collating, and a machine for closing filled envelopes.
In machines for inserting mail into envelopes, empty envelopes are presented successively in a filling position facing a mail transfer path. Each envelope is held in this filling position throughout the time taken to insert the mail into the envelope. Means are mounted on an envelope path for bringing each empty envelope to the filling position and for holding it there. These means may include a set of wheels and an associated set of backing wheels pressing thereagainst, with the envelopes being received between the sets which are disposed at the end of the mail transfer path. When driven, the set of wheels and the set of pressure backing wheels contribute to bringing each envelope into its filling position by driving the envelope body until the join line between the envelope body and the previously folded-back flap is received therebetween. The set of wheels is then no longer driven, the envelope comes to rest, and is held in the filling position facing the mail transfer path.
Envelope body opening fingers are used to open the body of the envelope held in the filling position in order to facilitate inserting the mail. These fingers are mounted at the front of the filling position and are normally retracted. In order to insert mail, they are actuated into an envelope body opening position and penetrate partially into the envelope body. In addition, the above-mentioned set of backing wheels is advantageously retractably mounted facing the set of wheels, and is put into the retracted position as soon a the set of wheels is no longer driven in order to allow the fingers in the opening position to take effect.
In prior insertion machines, various specific mechanism have also performed the mail insertion operation per se. They are intended in particular to enable the mail to be inserted right down to the end of the envelope. An example of one such mechanism is described, in particular, in French patent application No. 84 14 141 filed by the present Applicant. This mechanism includes an insertion plate mounted as a carriage which is driven with reciprocating motion. The insertion plate receives the mail to be inserted from the mail transfer path, then penetrates together with the mail held thereby into the envelope, after which it withdraws from the envelope, releasing the mail which it has been previously accompanied to the far end of the envelope. The use of such a mechanism and its control means give rise to machines which are relatively bulky. They are often difficult to manufacture and assemble given that it is desirable to house them in as small a volume as possible in order to reduce the bulk of the overall machine as much as possible.
The object of the present invention is to enable mail to be fully inserted into envelopes using a mechanism which is very simple and which avoids the above-mentioned drawbacks of bulkiness and difficulty of assembly.